Tracking the Quantified Self

We are data-generating and language-generating machines

Self-tracking is not really a tool of optimization but of discovery, and if tracking regimes that we would once have thought bizarre are becoming normal, one of the most interesting effects may be to make us re-evaluate what “normal” means.

—Gary Wolf, cofounder, The Quantified Self (The New York Times, 28 April 2010)

Illustration: Jesse Lefkowitz

For better or for worse, we are data-generating machines. Whenever we pay with a credit card or drive through an automated toll system, or answer an e-mail or make a phone call, we can’t help but leave a steady stream of ones and zeroes in our wake. This is our digital exhaust: the trackable or storable actions, choices, and preferences that we generate as we go about our daily lives. Even when just browsing the Web, we leave behind personal clickprints that uniquely identify our surfing behavior and lengthen the paperless trails that document our electronic selves.

From time to time, we harbor vague worries about oversharing on social networks or being tracked online by ad networks, but mostly we don’t think about the data shadows that we cast wherever we go. But there is a growing segment of the population that spends a remarkable amount of time and effort trying to generate more personal data. While the rest of us are content to step on a bathroom scale once a week, these people weigh themselves several times a day. You and I might groggily estimate the number of hours we slept last night, but these people wear sensors that tell them how many hours and minutes of REM and non-REM sleep they achieved.

I speak, of course, of self-trackers, people who use technology to acquire, store, and analyze their own life data. Their self-tracking can also create detailed records of food, exercise, location, and even mood, alertness, overall well-being, and other seemingly nonquantifiable psychological states. This process of self-digitization is often enhanced by smart clothing and other wearable computing technology that enables the self-monitoring of physiological states and self-sensing of such external data as location and time. These self-professed data junkies select from a variety of apps and websites that serve as tools for self-quantifying—and that prod them into doing even more of it. It is no wonder, then, that the movement as a whole is often called the quantified self (a term invented by Wired alums Gary Wolf and Kevin Kelly) and its practitioners are increasingly known as quantified-selfers or, simply, QSers.

You might think that the point of all this self-scrutiny is just to keep a record—that is, a lifelog—of vital stats, but self-trackers are not content with merely tracking a few numbers. Their interest lies in quantitative assessment: extracting knowledge from the raw data. They want to put their lives under the macroscope,which is the general term for any technology that enhances a person’s ability to gather and analyze data. If that data tells you that you’re just as bright-eyed and bushy-tailed on days when you managed only 5 or 6 hours of sleep, the lesson is clear: You’re one of those lucky people who don’t need 7 or 8 hours of sack time. If your heart rate and blood pressure spike when you sit down to dinner, maybe a little family counseling is in order. In short, by analyzing detailed data over a long period of time—either by generating charts in Excel or by using auto-analytics tools—self-trackers turn themselves into self-experimenters,perhaps even body hackers. The aim? Nothing more or less than the examined life, albeit one where “examined” means tracked, quantified, recorded, and analyzed.

But isn’t all this TMI (too much information)—narcissism for gadget freaks and data geeks? Are these sorts of overexamined lives worth living? Sorry, I don’t have enough data to answer those questions.